Design of jet grouted foundations for maritime structures

Jet grouting is a very popular ground improvement technique used all over the world for largely different applications. In maritime engineering it can be adopted for different purpose like subsoil reinforcement, protection from wave erosion, bottom and lateral sealing of excavations. Its main advantages consist in the relatively small spaces and light equipments required for the treatments execution and in the possibility of improving soil even below preexisting structures. However, since the results of treatments are influenced by the initial soil properties and cannot be fully predicted by theoretical relations, the design must be conducted by combining analytical models and experimental investigations. In the present paper the case of jet grouted foundation for near shore structures is treated, devoting a particular analysis to the case of horizontally loaded jet grouting columns. A theoretical method is introduced to perform an ultimate limit state analysis where the uncertainty arising from the variability of geometrical and mechanical properties is governed by means of probabilistic models. This approach represents a key for the planning of complementary experimental investigations.